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			<h1>Python <span class="color_h1">运算符</span></h1>
<hr><h2>什么是运算符？</h2>
<p>本章节主要说明Python的运算符。举个简单的例子<strong> 4 +5 = 9 </strong>。
例子中，<strong>4</strong> 和 <strong>5</strong> 被称为<strong>操作数</strong>，<span class="marked">+</span> 称为运算符。</p>
<p>Python语言支持以下类型的运算符:</p>
<ul>
<li><a href="#ysf1">算术运算符</a></li>
<li><a href="#ysf2">比较（关系）运算符</a></li>
<li><a href="#ysf3">赋值运算符</a></li>
<li><a href="#ysf4">逻辑运算符</a></li>
<li><a href="#ysf5">位运算符</a></li>
<li><a href="#ysf6">成员运算符</a></li>
<li><a href="#ysf7">身份运算符</a></li>
<li><a href="#ysf8">运算符优先级</a></li>
</ul>
<p>接下来让我们一个个来学习Python的运算符。</p><hr>
<h2 id="ysf1">Python算术运算符</h2>
<p>以下假设变量：<strong> a=10，b=20</strong>：</p>
<table class="reference">
<tbody><tr>
<th>运算符</th><th>描述</th><th>实例</th>
</tr>
<tr>
<td>+</td><td>加 - 两个对象相加</td><td> a + b 输出结果 30</td>
</tr>
<tr>
<td>-</td><td>减 - 得到负数或是一个数减去另一个数</td><td> a - b 输出结果 -10</td>
</tr>
<tr>
<td>*</td><td>乘 - 两个数相乘或是返回一个被重复若干次的字符串</td><td> a * b 输出结果 200</td>
</tr>
<tr>
<td>/</td><td>除 - x除以y</td><td> b / a 输出结果 2</td>
</tr>
<tr>
<td>%</td><td>取模 - 返回除法的余数</td><td> b % a 输出结果 0</td>
</tr>
<tr>
<td>**</td><td>幂 - 返回x的y次幂</td><td> a**b 为10的20次方， 输出结果 100000000000000000000</td>
</tr>
<tr>
<td>//</td><td>取整除 - 返回商的整数部分（<strong>向下取整</strong>）</td><td> 
<pre>&gt;&gt;&gt; 9//2
4
&gt;&gt;&gt; -9//2
-5</pre></td>
</tr>
</tbody></table>

<p>以下实例演示了Python所有算术运算符的操作：</p>

<div class="example"> 
<h2 class="example">实例(Python 2.0+)</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">21</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">10</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> + </span><span class="hl-identifier">b</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> - </span><span class="hl-identifier">b</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code"> 
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> * </span><span class="hl-identifier">b</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code"> 
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> / </span><span class="hl-identifier">b</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">4 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code"> 
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> % </span><span class="hl-identifier">b</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">5 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-comment"># 修改变量 a 、b 、c</span><span class="hl-code">
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">2</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">3</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code">**</span><span class="hl-identifier">b</span><span class="hl-code"> 
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">6 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">10</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">5</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code">//</span><span class="hl-identifier">b</span><span class="hl-code"> 
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">7 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span></div>
</div><br>
<a target="_blank" href="../try/runcode.php?filename=test_operator&type=python" class="showbtn" rel="noopener noreferrer">运行实例 »</a>
</div>

<p>以上实例输出结果：</p>
<pre>
1 - c 的值为： 31
2 - c 的值为： 11
3 - c 的值为： 210
4 - c 的值为： 2
5 - c 的值为： 1
6 - c 的值为： 8
7 - c 的值为： 2
</pre>

<blockquote>
<p><strong>注意：</strong>Python2.x 里，整数除整数，只能得出整数。如果要得到小数部分，把其中一个数改成浮点数即可。</p>
<pre>
&gt;&gt;&gt; 1/2
0
&gt;&gt;&gt; 1.0/2
0.5
&gt;&gt;&gt; 1/float(2)
0.5
</pre></blockquote>


<hr><h2 id="ysf2">Python比较运算符</h2>
<p>以下假设变量a为10，变量b为20：</p>
<table class="reference">
<tbody><tr>
<th width="10%">运算符</th><th>描述</th><th>实例</th>
</tr>
<tr>
<td>==</td><td> 等于 - 比较对象是否相等</td><td> (a == b) 返回 False。 </td>
</tr>
<tr>
<td>!=</td><td> 不等于 - 比较两个对象是否不相等</td><td> (a != b) 返回 True。 </td>
</tr>
<tr>
<td>&lt;&gt;</td><td>不等于 -  比较两个对象是否不相等。<span class="important">python3 已废弃。</span></td><td> (a &lt;&gt; b) 返回 True。这个运算符类似 != 。</td>
</tr>
<tr>
<td>&gt;</td><td> 大于 - 返回x是否大于y</td><td> (a &gt; b) 返回 False。</td>
</tr>
<tr>
<td>&lt;</td><td> 小于 - 返回x是否小于y。所有比较运算符返回1表示真，返回0表示假。这分别与特殊的变量 True 和 False 等价。</td><td> (a &lt; b) 返回 True。 </td>
</tr>
<tr>
<td>&gt;=</td><td> 大于等于	- 返回x是否大于等于y。</td><td> (a &gt;= b) 返回 False。</td>

</tr>
<tr>
<td>&lt;=</td><td> 小于等于 -	返回x是否小于等于y。</td><td> (a &lt;= b) 返回 True。 </td>
</tr>
</tbody></table>
<p>以下实例演示了Python所有比较运算符的操作：</p>
<div class="example"> 
<h2 class="example">实例(Python 2.0+)</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">21</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">10</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">
 
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">a</span><span class="hl-code"> == </span><span class="hl-identifier">b</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - a 等于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - a 不等于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">a</span><span class="hl-code"> != </span><span class="hl-identifier">b</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - a 不等于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - a 等于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">a</span><span class="hl-code"> &lt;&gt; </span><span class="hl-identifier">b</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - a 不等于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - a 等于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">a</span><span class="hl-code"> &lt; </span><span class="hl-identifier">b</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">4 - a 小于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code"> 
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">4 - a 大于等于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">a</span><span class="hl-code"> &gt; </span><span class="hl-identifier">b</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">5 - a 大于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">5 - a 小于等于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-comment"># 修改变量 a 和 b 的值</span><span class="hl-code">
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">5</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">20</span><span class="hl-code">
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">a</span><span class="hl-code"> &lt;= </span><span class="hl-identifier">b</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">6 - a 小于等于 b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">6 - a 大于  b</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">b</span><span class="hl-code"> &gt;= </span><span class="hl-identifier">a</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">7 - b 大于等于 a</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">7 - b 小于 a</span><span class="hl-quotes">&quot;</span></div>
</div></div>

<p>以上实例输出结果：</p>
<pre>
1 - a 不等于 b
2 - a 不等于 b
3 - a 不等于 b
4 - a 大于等于 b
5 - a 大于 b
6 - a 小于等于 b
7 - b 大于等于 a
</pre> 
<hr><h2 id="ysf3">Python赋值运算符</h2> 
<p>以下假设变量a为10，变量b为20：</p>
<table class="reference">
<tbody><tr>
<th>运算符</th><th>描述</th><th>实例</th>
</tr>
<tr>
<td>=</td><td>简单的赋值运算符</td><td> c = a + b 将 a + b 的运算结果赋值为 c</td>
</tr>
<tr>
<td>+=</td><td>加法赋值运算符</td><td> c += a 等效于 c = c + a</td>
</tr>
<tr>
<td>-=</td><td>减法赋值运算符</td><td> c -= a 等效于 c = c - a</td>
</tr>
<tr>
<td>*=</td><td>乘法赋值运算符</td><td> c *= a 等效于 c = c * a</td>
</tr>
<tr>
<td>/=</td><td>除法赋值运算符</td><td> c /= a 等效于 c = c / a</td>
</tr>
<tr>
<td>%=</td><td>取模赋值运算符</td><td> c %= a 等效于 c = c % a</td>
</tr>
<tr>
<td>**=</td><td>幂赋值运算符</td><td> c **= a 等效于 c = c ** a</td>
</tr>
<tr>
<td>//=</td><td> 取整除赋值运算符</td><td> c //= a 等效于 c = c // a</td>
</tr>
</tbody></table>
<p>以下实例演示了Python所有赋值运算符的操作：</p>
<div class="example"> 
<h2 class="example">实例(Python 2.0+)</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">21</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">10</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> + </span><span class="hl-identifier">b</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> += </span><span class="hl-identifier">a</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code"> 
 
</span><span class="hl-identifier">c</span><span class="hl-code"> *= </span><span class="hl-identifier">a</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code"> 
 
</span><span class="hl-identifier">c</span><span class="hl-code"> /= </span><span class="hl-identifier">a</span><span class="hl-code"> 
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">4 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code"> 
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-number">2</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code"> %= </span><span class="hl-identifier">a</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">5 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> **= </span><span class="hl-identifier">a</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">6 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> //= </span><span class="hl-identifier">a</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">7 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span></div>
</div></div>
<p>以上实例输出结果：</p>
<pre>
1 - c 的值为： 31
2 - c 的值为： 52
3 - c 的值为： 1092
4 - c 的值为： 52
5 - c 的值为： 2
6 - c 的值为： 2097152
7 - c 的值为： 99864
</pre>
<hr><h2 id="ysf5">Python位运算符</h2> 
<p>
按位运算符是把数字看作二进制来进行计算的。Python中的按位运算法则如下：</p>
<p>下表中变量 a 为 60，b 为 13，二进制格式如下：</p>
<pre>
a = 0011 1100

b = 0000 1101

-----------------

a&amp;b = 0000 1100

a|b = 0011 1101

a^b = 0011 0001

~a  = 1100 0011
</pre>
<table class="reference">
<tbody><tr>
<th>运算符</th><th>描述</th><th>实例</th>
</tr>
<tr>
<td>&amp;</td><td>按位与运算符：参与运算的两个值,如果两个相应位都为1,则该位的结果为1,否则为0</td><td> (a &amp; b) 输出结果 12 ，二进制解释： 0000 1100</td>
</tr>
<tr>
<td>|</td><td> 按位或运算符：只要对应的二个二进位有一个为1时，结果位就为1。</td><td> (a | b) 输出结果 61 ，二进制解释： 0011 1101</td>
</tr>
<tr>
<td>^</td><td>按位异或运算符：当两对应的二进位相异时，结果为1 </td><td> (a ^ b) 输出结果 49 ，二进制解释： 0011 0001</td>
</tr>
<tr>
<td>~</td><td> 按位取反运算符：对数据的每个二进制位取反,即把1变为0,把0变为1 。<span class="marked">~x</span> 类似于 <span class="marked">-x-1</span></td><td> (~a ) 输出结果 -61 ，二进制解释： 1100 0011，在一个有符号二进制数的补码形式。</td>
</tr>
<tr>
<td>&lt;&lt;</td><td>左移动运算符：运算数的各二进位全部左移若干位，由 <span class="marked">&lt;&lt;</span> 右边的数字指定了移动的位数，高位丢弃，低位补0。</td><td> a &lt;&lt; 2 输出结果 240 ，二进制解释： 1111 0000</td>
</tr>
<tr>
<td>&gt;&gt;</td><td>右移动运算符：把"&gt;&gt;"左边的运算数的各二进位全部右移若干位，<span class="marked">&gt;&gt;</span> 右边的数字指定了移动的位数 </td><td> a &gt;&gt; 2 输出结果 15 ，二进制解释： 0000 1111</td>
</tr>
</tbody></table>
<p>以下实例演示了Python所有位运算符的操作：</p>
<div class="example"> 
<h2 class="example">实例(Python 2.0+)</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">60</span><span class="hl-code">            </span><span class="hl-comment"># 60 = 0011 1100 </span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">13</span><span class="hl-code">            </span><span class="hl-comment"># 13 = 0000 1101 </span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> &amp; </span><span class="hl-identifier">b</span><span class="hl-code">;        </span><span class="hl-comment"># 12 = 0000 1100</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> | </span><span class="hl-identifier">b</span><span class="hl-code">;        </span><span class="hl-comment"># 61 = 0011 1101 </span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> ^ </span><span class="hl-identifier">b</span><span class="hl-code">;        </span><span class="hl-comment"># 49 = 0011 0001</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = ~</span><span class="hl-identifier">a</span><span class="hl-code">;           </span><span class="hl-comment"># -61 = 1100 0011</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">4 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> &lt;&lt; </span><span class="hl-number">2</span><span class="hl-code">;       </span><span class="hl-comment"># 240 = 1111 0000</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">5 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> &gt;&gt; </span><span class="hl-number">2</span><span class="hl-code">;       </span><span class="hl-comment"># 15 = 0000 1111</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">6 - c 的值为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">c</span></div>
</div></div>
<p>以上实例输出结果：</p>
<pre>
1 - c 的值为： 12
2 - c 的值为： 61
3 - c 的值为： 49
4 - c 的值为： -61
5 - c 的值为： 240
6 - c 的值为： 15
</pre>
<hr><h2 id="ysf4">Python逻辑运算符</h2>
<p>Python语言支持逻辑运算符，以下假设变量 a 为 10, b为 20:</p>

<table class="reference">
<tbody><tr>
<th>运算符</th><th>逻辑表达式</th><th>描述</th><th>实例</th>
</tr>
<tr>
<td>and</td><td>x and y</td><td> 布尔"与" - 如果 x 为 False，x and y 返回 False，否则它返回 y 的计算值。	</td><td> (a and b) 返回 20。</td>
</tr>
<tr>
<td>or</td><td>x or y</td><td>布尔"或"	- 如果 x 是非 0，它返回 x 的计算值，否则它返回 y 的计算值。</td><td> (a or b) 返回 10。</td>
</tr>
<tr><td>not</td><td>not x</td><td>布尔"非" - 如果 x 为 True，返回 False 。如果 x 为 False，它返回 True。</td><td> not(a and b) 返回 False </td>
</tr>
</tbody></table>
<p>以上实例输出结果：</p>
<div class="example"> 
<h2 class="example">实例(Python 2.0+)</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">10</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">20</span><span class="hl-code">
 
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">and</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - 变量 a 和 b 都为 True</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - 变量 a 和 b 有一个不为 True</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">or</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - 变量 a 和 b 都为 True，或其中一个变量为 True</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - 变量 a 和 b 都不为 True</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-comment"># 修改变量 a 的值</span><span class="hl-code">
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">and</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - 变量 a 和 b 都为 True</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - 变量 a 和 b 有一个不为 True</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-reserved">if</span><span class="hl-code">  </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">or</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code"> :
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">4 - 变量 a 和 b 都为 True，或其中一个变量为 True</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">4 - 变量 a 和 b 都不为 True</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-reserved">if</span><span class="hl-code"> </span><span class="hl-identifier">not</span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">and</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code"> </span><span class="hl-brackets">)</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">5 - 变量 a 和 b 都为 False，或其中一个变量为 False</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">5 - 变量 a 和 b 都为 True</span><span class="hl-quotes">&quot;</span></div>
</div></div>
<p>以上实例输出结果：</p>
<pre>
1 - 变量 a 和 b 都为 True
2 - 变量 a 和 b 都为 True，或其中一个变量为 True
3 - 变量 a 和 b 有一个不为 True
4 - 变量 a 和 b 都为 True，或其中一个变量为 True
5 - 变量 a 和 b 都为 False，或其中一个变量为 False
</pre>
<hr><h2 id="ysf6">Python成员运算符</h2> 
<p>除了以上的一些运算符之外，Python还支持成员运算符，测试实例中包含了一系列的成员，包括字符串，列表或元组。</p>
<table class="reference">
<tbody><tr>
<th>运算符</th><th>描述</th><th>实例</th>
</tr>
<tr>
<td>in</td><td>
如果在指定的序列中找到值返回 True，否则返回 False。</td>
<td> x 在 y 序列中 , 如果 x 在 y 序列中返回 True。</td>
</tr>
<tr>
<td>not in</td><td>如果在指定的序列中没有找到值返回 True，否则返回 False。</td>
<td>x 不在 y 序列中 , 如果 x 不在 y 序列中返回 True。</td>
</tr>
</tbody></table>
<p>以下实例演示了Python所有成员运算符的操作：</p>
<div class="example"> 
<h2 class="example">实例(Python 2.0+)</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">10</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">20</span><span class="hl-code">
</span><span class="hl-identifier">list</span><span class="hl-code"> = </span><span class="hl-brackets">[</span><span class="hl-number">1</span><span class="hl-code">, </span><span class="hl-number">2</span><span class="hl-code">, </span><span class="hl-number">3</span><span class="hl-code">, </span><span class="hl-number">4</span><span class="hl-code">, </span><span class="hl-number">5</span><span class="hl-code"> </span><span class="hl-brackets">]</span><span class="hl-code">;
 
</span><span class="hl-identifier">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">in</span><span class="hl-code"> </span><span class="hl-identifier">list</span><span class="hl-code"> </span><span class="hl-brackets">)</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - 变量 a 在给定的列表中 list 中</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - 变量 a 不在给定的列表中 list 中</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-identifier">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code"> </span><span class="hl-reserved">not</span><span class="hl-code"> </span><span class="hl-reserved">in</span><span class="hl-code"> </span><span class="hl-identifier">list</span><span class="hl-code"> </span><span class="hl-brackets">)</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - 变量 b 不在给定的列表中 list 中</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - 变量 b 在给定的列表中 list 中</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-comment"># 修改变量 a 的值</span><span class="hl-code">
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">2</span><span class="hl-code">
</span><span class="hl-identifier">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">in</span><span class="hl-code"> </span><span class="hl-identifier">list</span><span class="hl-code"> </span><span class="hl-brackets">)</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - 变量 a 在给定的列表中 list 中</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - 变量 a 不在给定的列表中 list 中</span><span class="hl-quotes">&quot;</span></div>
</div></div>
<p>以上实例输出结果：</p>
<pre>
1 - 变量 a 不在给定的列表中 list 中
2 - 变量 b 不在给定的列表中 list 中
3 - 变量 a 在给定的列表中 list 中
</pre>
<hr><h2 id="ysf7">Python身份运算符</h2>
<p> 
身份运算符用于比较两个对象的存储单元</p>
<table class="reference">
<tbody><tr>
<th width="10%">运算符</th><th>描述</th><th>实例</th>
</tr>
<tr>
<td>is</td><td>
is 是判断两个标识符是不是引用自一个对象</td><td> <strong>x is y</strong>, 类似 <strong>id(x) == id(y)</strong> , 如果引用的是同一个对象则返回 True，否则返回 False</td>
</tr>
<tr>
<td>is not</td><td>is not 是判断两个标识符是不是引用自不同对象</td><td><strong> x is not y</strong> ， 类似 <strong>id(a) != id(b)</strong>。如果引用的不是同一个对象则返回结果 True，否则返回 False。 </td>
</tr>
</tbody></table>
<p><strong>注：</strong> <a href="../python/python-func-id.html" target="_blank" rel="noopener noreferrer">id()</a> 函数用于获取对象内存地址。</p>
<p>以下实例演示了Python所有身份运算符的操作：</p>
<div class="example"> 
<h2 class="example">实例(Python 2.0+)</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">20</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">20</span><span class="hl-code">
 
</span><span class="hl-identifier">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">is</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code"> </span><span class="hl-brackets">)</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - a 和 b 有相同的标识</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">1 - a 和 b 没有相同的标识</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-identifier">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">is</span><span class="hl-code"> </span><span class="hl-reserved">not</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code"> </span><span class="hl-brackets">)</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - a 和 b 没有相同的标识</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">2 - a 和 b 有相同的标识</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-comment"># 修改变量 b 的值</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">30</span><span class="hl-code">
</span><span class="hl-identifier">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">is</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code"> </span><span class="hl-brackets">)</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - a 和 b 有相同的标识</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">3 - a 和 b 没有相同的标识</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-identifier">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">is</span><span class="hl-code"> </span><span class="hl-reserved">not</span><span class="hl-code"> </span><span class="hl-identifier">b</span><span class="hl-code"> </span><span class="hl-brackets">)</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">4 - a 和 b 没有相同的标识</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-reserved">else</span><span class="hl-code">:
   </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">4 - a 和 b 有相同的标识</span><span class="hl-quotes">&quot;</span></div>
</div></div>
<p>以上实例输出结果：</p>
<pre>
1 - a 和 b 有相同的标识
2 - a 和 b 有相同的标识
3 - a 和 b 没有相同的标识
4 - a 和 b 没有相同的标识
</pre>

<blockquote>
<p>is 与 == 区别：</p>
<p>is 用于判断两个变量引用对象是否为同一个(同一块内存空间)， == 用于判断引用变量的值是否相等。</p>
<pre>
&gt;&gt;&gt; a = [1, 2, 3]
&gt;&gt;&gt; b = a
&gt;&gt;&gt; b is a 
True
&gt;&gt;&gt; b == a
True
&gt;&gt;&gt; b = a[:]
&gt;&gt;&gt; b is a
False
&gt;&gt;&gt; b == a
True
</pre></blockquote>



<hr><h2 id="ysf8">Python运算符优先级</h2>
<p>以下表格列出了从最高到最低优先级的所有运算符：</p>
<table class="reference">
<tbody><tr><th>运算符</th><th>描述</th></tr>
<tr>
<td>**</td>
<td>指数 (最高优先级)</td>
</tr><tr>
<td>~ + -</td>
<td>按位翻转, 一元加号和减号 (最后两个的方法名为 +@ 和 -@)</td>
</tr><tr>
<td>* / % //</td>
<td>乘，除，取模和取整除</td>
</tr><tr>
<td>+ -</td>
<td>加法减法</td>
</tr><tr>
<td>&gt;&gt; &lt;&lt;</td>
<td>右移，左移运算符</td>
</tr><tr>
<td>&amp;</td>
<td>位 'AND'</td>
</tr><tr>
<td>^ |</td>
<td>位运算符</td>
</tr><tr>
<td>&lt;= &lt; &gt; &gt;=</td>
<td>比较运算符</td>
</tr><tr>
<td>&lt;&gt; == !=</td>
<td>等于运算符</td>
</tr>
<tr>
<td>= %= /= //= -= += *= **=</td>
<td>赋值运算符</td>
</tr>
<tr>
<td>is is not</td>
<td>身份运算符</td>
</tr>
<tr>
<td>in not in</td>
<td>成员运算符</td>
</tr><tr>
<td>not and or</td>
<td>逻辑运算符</td>
</tr>
</tbody></table>

<p>以下实例演示了Python所有运算符优先级的操作：</p>
<div class="example"> 
<h2 class="example">实例(Python 2.0+)</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-number">20</span><span class="hl-code">
</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-number">10</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-number">15</span><span class="hl-code">
</span><span class="hl-identifier">d</span><span class="hl-code"> = </span><span class="hl-number">5</span><span class="hl-code">
</span><span class="hl-identifier">e</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">
 
</span><span class="hl-identifier">e</span><span class="hl-code"> = </span><span class="hl-brackets">(</span><span class="hl-identifier">a</span><span class="hl-code"> + </span><span class="hl-identifier">b</span><span class="hl-brackets">)</span><span class="hl-code"> * </span><span class="hl-identifier">c</span><span class="hl-code"> / </span><span class="hl-identifier">d</span><span class="hl-code">       </span><span class="hl-comment">#( 30 * 15 ) / 5</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">(a + b) * c / d 运算结果为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">,  </span><span class="hl-identifier">e</span><span class="hl-code">
 
</span><span class="hl-identifier">e</span><span class="hl-code"> = </span><span class="hl-brackets">(</span><span class="hl-brackets">(</span><span class="hl-identifier">a</span><span class="hl-code"> + </span><span class="hl-identifier">b</span><span class="hl-brackets">)</span><span class="hl-code"> * </span><span class="hl-identifier">c</span><span class="hl-brackets">)</span><span class="hl-code"> / </span><span class="hl-identifier">d</span><span class="hl-code">     </span><span class="hl-comment"># (30 * 15 ) / 5</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">((a + b) * c) / d 运算结果为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">,  </span><span class="hl-identifier">e</span><span class="hl-code">
 
</span><span class="hl-identifier">e</span><span class="hl-code"> = </span><span class="hl-brackets">(</span><span class="hl-identifier">a</span><span class="hl-code"> + </span><span class="hl-identifier">b</span><span class="hl-brackets">)</span><span class="hl-code"> * </span><span class="hl-brackets">(</span><span class="hl-identifier">c</span><span class="hl-code"> / </span><span class="hl-identifier">d</span><span class="hl-brackets">)</span><span class="hl-code">;    </span><span class="hl-comment"># (30) * (15/5)</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">(a + b) * (c / d) 运算结果为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">,  </span><span class="hl-identifier">e</span><span class="hl-code">
 
</span><span class="hl-identifier">e</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code"> + </span><span class="hl-brackets">(</span><span class="hl-identifier">b</span><span class="hl-code"> * </span><span class="hl-identifier">c</span><span class="hl-brackets">)</span><span class="hl-code"> / </span><span class="hl-identifier">d</span><span class="hl-code">;      </span><span class="hl-comment">#  20 + (150/5)</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">a + (b * c) / d 运算结果为：</span><span class="hl-quotes">&quot;</span><span class="hl-code">,  </span><span class="hl-identifier">e</span></div>
</div></div>
<p>以上实例输出结果：</p>
<pre>
(a + b) * c / d 运算结果为： 90
((a + b) * c) / d 运算结果为： 90
(a + b) * (c / d) 运算结果为： 90
a + (b * c) / d 运算结果为： 50
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		<li class="comment even thread-even depth-1" id="comment-13261"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;CosmosHua</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;cos***cosmos@163.com</p></div><div id="runoobvote-id-13261" data-commid = "13261" class="upvotejs"><a class="upvote"></a> <span class="count">246</span></div></div><div class="comt-main" id="div-comment-13261">

<blockquote><p>以下测试情况会在交互模式下出现，脚本模式 is 和 == 结果是一样的。</p></blockquote>


<p>python中会为每个出现的对象分配内存，哪怕他们的值完全相等（注意是相等不是相同）。如执行a=2.0，b=2.0这两个语句时会先后为2.0这个Float类型对象分配内存，然后将a与b分别指向这两个对象。所以a与b指向的不是同一对象：</p><pre>&gt;&gt;&gt; a=2.0
&gt;&gt;&gt; b=2.0
&gt;&gt;&gt; a is b
False
&gt;&gt;&gt; a==b
True
&gt;&gt;&gt; e</pre><p>但是为了提高内存利用效率对于一些简单的对象，如一些数值较小的int对象，python采取重用对象内存的办法，如指向a=2，b=2时，由于2作为简单的int类型且数值小，python不会两次为其分配内存，而是只分配一次，然后将a与b同时指向已分配的对象：</p><pre>&gt;&gt;&gt; a=2
&gt;&gt;&gt; b=2
&gt;&gt;&gt; a is b
True
&gt;&gt;&gt; a==b
True</pre><p> 如但果赋值的不是2而是大的数值，情况就跟前面的一样了：</p><pre>
&gt;&gt;&gt; a=4444
&gt;&gt;&gt; b=4444
&gt;&gt;&gt; a is b
False
&gt;&gt;&gt; a==b
True</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">CosmosHua</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;CosmosHua</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;cos***cosmos@163.com</p></div></span>6年前 (2017-06-23)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-13747"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Gy_GDUT</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;634***603@qq.com</p></div><div id="runoobvote-id-13747" data-commid = "13747" class="upvotejs"><a class="upvote"></a> <span class="count">65</span></div></div><div class="comt-main" id="div-comment-13747"><p>这里 <span class="marked">is</span> 和 <span class="marked">==</span> 类似编译原理中传值与传地址。又或者说是 <span class="marked">is</span> 只是传递的指针，判断是否指向同一个地址块，这样 <span class="marked">is</span> 两边的参数指向内存中同个地址块，毕竟我家电视跟你电视不是同一个东西。而 <span class="marked">==</span> 则是仅仅判断值相同</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">Gy_GDUT</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Gy_GDUT</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;634***603@qq.com</p></div></span>6年前 (2017-07-06)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-14016"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;gjxie</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;130***2297@qq.com</p></div><div id="runoobvote-id-14016" data-commid = "14016" class="upvotejs"><a class="upvote"></a> <span class="count">149</span></div></div><div class="comt-main" id="div-comment-14016"><p>如果变量写在同一行,将会指向同一个对象</p><pre>&gt;&gt;&gt; a=4444; b=4444;   # 写在同一行
&gt;&gt;&gt; a is b
True
&gt;&gt;&gt; a == b
True

&gt;&gt;&gt; c = 5555   # 写在不同一行
&gt;&gt;&gt; d = 5555   # 写在不同一行
&gt;&gt;&gt; c is d
False
&gt;&gt;&gt; c == d
True
&gt;&gt;&gt; 
</pre>
<p>以上情况在交互模式会出现，使用脚本运行，不管是否同一行，都是指向同一个地址：</p>
<pre># -*- coding: utf-8 -*-

a = 4444; b = 4444
print(a is b)          # true

c = 5555
d = 5555
print(c is d)          # true</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">gjxie</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;gjxie</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;130***2297@qq.com</p></div></span>6年前 (2017-07-13)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-24457"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;冯姜澎</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;101***9418@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="http://bbs.csdn.net/topics/392272350?page=1">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-24457" data-commid = "24457" class="upvotejs"><a class="upvote"></a> <span class="count">73</span></div></div><div class="comt-main" id="div-comment-24457"><p data-title="关于 Pyhton中没有自增自减运算符的说明"><strong>Python 中没有 ++ 或 -- 自运算符</strong></p>

<p>因为在 Python 里的数值和字符串之类的都是不可变对象，对不可变对象操作的结果都会生成一个新的对象。</p>

<p>比如：</p>

<pre>a = 1
a += 1</pre>

<p>在 C/java 之类的语言中，把 a 指向内存地址单元数据值由 1 改成了 2。</p>

<p>但是在 Python 中是完全不同的另一套机制。</p>

<p>解释器创建一个新的整数对象 2。</p>

<p>然后把这个对象的地址再次分配给 a。</p>

<p>见下面代码:</p>



<pre>&gt;&gt;&gt; id(1)
41116008L
&gt;&gt;&gt; a = 1
&gt;&gt;&gt; id(a)
41116008L
&gt;&gt;&gt; id(2)
41115984L
&gt;&gt;&gt;a += 1
&gt;&gt;&gt; id(a)
41115984L
&gt;&gt;&gt; </pre>

<p>所以在 Python 中不可能出现C/java  之类那种单独一行一个 <span class="marked">i++</span>，<span class="marked">i--</span> 的。</p>

<div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="../note/24457">冯姜澎</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;冯姜澎</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;101***9418@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="http://bbs.csdn.net/topics/392272350?page=1">&nbsp;&nbsp;参考地址</a></p></div></span>5年前 (2018-02-28)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-29970"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;广工陈不亮</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;113***2936@qq.com</p></div><div id="runoobvote-id-29970" data-commid = "29970" class="upvotejs"><a class="upvote"></a> <span class="count">96</span></div></div><div class="comt-main" id="div-comment-29970"><p>Python 基础的发现个问题，有一个列表 <span class="marked">a=[1,2,3,4,5]</span>，赋值给 <strong>b</strong> 的两种方式：</p>

<pre># 第一种
b=a 

# 第一种
b=a[:]</pre>

<p>结果都是: <strong>[1, 2, 3, 4, 5]</strong></p>

<p><strong>这两种赋值结果看起来都是一样的，但是他们有什么区别么？</strong></p>

<p>区别就是:</p>
<ul><li>
前者传递引用
</li><li>
后者是拷贝
</li></ul>
<p>Python 有个叫做 <strong>id</strong> 的函数能够得到对象的地址，你打印出来看看就清楚了。直接 <strong>=</strong> 是引用赋值，引用原来的对象；而 <span class="marked">[:]</span> 是重新推导，会生成新的对象。</p>

<pre>&gt;&gt;&gt; a=[1,2,3,4,5]
&gt;&gt;&gt; b=a
&gt;&gt;&gt; c=a[:]
&gt;&gt;&gt; id(a)
4410359536
&gt;&gt;&gt; id(b)
4410359536
&gt;&gt;&gt; id(c)
4410358240
</pre>
<p>从以上结果上看 id(a) 与 id(b) 的内存地址一样的，而 id(a) 与 id(c) 内存地址不一样。</p>
<div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">广工陈不亮</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;广工陈不亮</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;113***2936@qq.com</p></div></span>5年前 (2018-07-21)</div></div></li><!-- #comment-## -->
<li class="comment byuser comment-author-tianqixin bypostauthor odd alt thread-odd thread-alt depth-1" id="comment-30059"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;BNG</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;459***40967@qq.com</p></div><div id="runoobvote-id-30059" data-commid = "30059" class="upvotejs"><a class="upvote"></a> <span class="count">24</span></div></div><div class="comt-main" id="div-comment-30059"><p>自上而下，<strong>优先级逐步提高</strong>。</p>

<table class="reference"><tbody><tr><th align="center">运算符</th>
<th align="center">描述</th>
</tr><tr><td>lambda</td>
<td>Lambda 表达式（优先级最低）</td>
</tr><tr><td>or</td>
<td>布尔“或”</td>
</tr><tr><td>and</td>
<td>布尔“与”</td>
</tr><tr><td>not x</td>
<td>布尔“非”</td>
</tr><tr><td>in，not in</td>
<td>成员测试</td>
</tr><tr><td>is，is not</td>
<td>同一性测试</td>
</tr><tr><td>&lt;，&lt;=，&gt;，&gt;=，!=，==</td>
<td>比较</td>
</tr><tr><td>|</td>
<td>按位或</td>
</tr><tr><td>^</td>
<td>按位异或</td>
</tr><tr><td>&amp;</td>
<td>按位与</td>
</tr><tr><td>&lt;&lt;，&gt;&gt;</td>
<td>移位</td>
</tr><tr><td>+，-</td>
<td>加法与减法</td>
</tr><tr><td>*，/，%</td>
<td>乘法、除法与取余</td>
</tr><tr><td>+x，-x</td>
<td>正负号</td>
</tr><tr><td>~x</td>
<td>按位翻转</td>
</tr><tr><td>**</td>
<td>指数</td>
</tr><tr><td>x.attribute</td>
<td>属性参考</td>
</tr><tr><td>x[index]</td>
<td>下标</td>
</tr><tr><td>x[index:index]</td>
<td>寻址段</td>
</tr><tr><td>f(arguments...)</td>
<td>函数调用</td>
</tr><tr><td>(experession,...)</td>
<td>绑定或元组显示</td>
</tr><tr><td>[expression,...]</td>
<td>列表显示</td>
</tr><tr><td>{key:datum,...}</td>
<td>字典显示</td>
</tr><tr><td>'expression,...'（优先级最高）</td>
<td>字符串转换</td>
</tr></tbody></table><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">BNG</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;BNG</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;459***40967@qq.com</p></div></span>5年前 (2018-07-23)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-33502"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;jt</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;jun***hu1995@163.com</p></div><div id="runoobvote-id-33502" data-commid = "33502" class="upvotejs"><a class="upvote"></a> <span class="count">46</span></div></div><div class="comt-main" id="div-comment-33502"><p data-title="Python is 与 == 区别" data-commid="13261, 13747, 14016"><strong>is 与 == 区别 ：</strong></p>

<p><strong>is</strong> 用于判断两个变量引用对象是否为同一个， <strong>==</strong> 用于判断引用变量的值是否相等。</p>

<p><span class="marked">a is b</span> 相当于 <span class="marked">id(a)==id(b)</span>，<strong>id()</strong> 能够获取对象的内存地址。</p>

<p>如果 a=10;b=a; 则此时 a 和 b 的内存地址一样的;</p>

<p>但当 a=[1,2,3]; 另 b=a[:] 时，虽然 a 和 b 的值一样，但内存地址不一样。</p>

<p>如果此时定义 a=10、b=10, 然后再对比 a is b 会发现返回的结果是 True，这是因为在 Python 中会实现创建一个小型的整形池，范围为 [-5,256]，为这些整形开辟好内存空间，当代码中定义该范围内的整形时，不会再重新分配内存地址。而我在 Pycharm 中进行测试：</p>

<pre>
#coding=utf-8
a=100000000000;
b=100000000000;
print a is b
</pre>
<p>结果：</p> 
<pre>True</pre>
<p>后来查了资料才发现是：Python出于对性能的考虑，但凡是不可变对象，在同一个代码块中的对象，只有是值相同的对象，就不会重复创建，而是直接引用已经存在的对象。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="../note/33502">jt</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;jt</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;jun***hu1995@163.com</p></div></span>5年前 (2018-08-02)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-48315"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Rounie</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;zha***51282436@sina.com</p></div><div id="runoobvote-id-48315" data-commid = "48315" class="upvotejs"><a class="upvote"></a> <span class="count">89</span></div></div><div class="comt-main" id="div-comment-48315"><p><strong>回复一楼：</strong></p>
<p>
验证了一楼的回答，正如其所说，python 中用 is 关键字判断两个小一点数，的确和 == 运算符一样，结果同为 true，但是这个小一点数取值到底小到多少，上限多少，经过测试，当数小于等于 256 时，两者结果相同，大于 256 后，is 判断结果就为 false 了。</p>

<p>本人猜测：256 刚好为 8 为二进制数，是一个字节，所以可以归纳为当数可以用一个字节来表示时，is 和 == 结果相同，当数超过一个字节时，按不同对象来对待，python 为不同数分配了不同内存，不同数为不同的对象，只是值相同而已，is 结果为 false，== 依然为 true。</p>

<p>看了楼上回答，才明白 python 创建了一个小型整型池来存放这些可以用一个字节表示的数，这样做避免了为小点数值重复分配内存，也即重复创建对象，提高了语言运行性能。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">Rounie</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Rounie</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;zha***51282436@sina.com</p></div></span>4年前 (2019-11-11)</div></div></li><!-- #comment-## -->
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		<p><a href="../w3cnote/runoob-user-test-intro.html#invite" target="_blank">注册邀请码获取方式</a></p>-->
	</div>
		
	<form action="/wp-content/themes/runoob/option/addnote.php" method="post" id="commentform" style="display:none;">
		<div class="comt">
			<div class="comt-title">
				<i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i>				<p><a id="cancel-comment-reply-link" href="javascript:;">取消</a></p>
			</div>
			<div class="comt-box">
			<div id="mded"></div>
			
				<div class="comt-ctrl">
					<div class="comt-tips"><input type='hidden' name='comment_post_ID' value='4014' id='comment_post_ID' />
<input type='hidden' name='comment_parent' id='comment_parent' value='0' />
</div>
					<button type="submit" name="submit" id="submit" tabindex="5"><i class="fa fa-pencil" aria-hidden="true"></i> 分享笔记</button>
				</div>
			</div>
		
				
					<div class="comt-comterinfo"> 
						<ul id="comment-author-info">
							<li class="form-inline"><label class="hide" for="author">昵称</label><input class="ipt" type="text" name="author" id="author" value="" tabindex="2" placeholder="昵称"><span class="text-muted">昵称 (必填)</span></li>
							<li class="form-inline"><label class="hide" for="email">邮箱</label><input class="ipt" type="text" name="email" id="email" value="" tabindex="3" placeholder="邮箱"><span class="text-muted">邮箱 (必填)</span></li>
							<li class="form-inline"><label class="hide" for="url">引用地址</label><input class="ipt" type="text" name="url" id="url" value="" tabindex="4" placeholder="引用地址"><span class="text-muted">引用地址</span></li>
						</ul>
					</div>
				
			
		</div>

	</form>
	</div>
<script type="text/javascript">
$(function() {
	//初始化编辑器
	
	var editor = new Simditor({
	  textarea: $('#mded'),
	  placeholder: '写笔记...',
	  upload:false,
	 // upload: {url:'/api/comment_upload_file.php',params: null,fileKey: 'upload_file',connectionCount: 1,leaveConfirm: '文件正在上传，您确定离开?'},
	  defaultImage: 'https://www.runoob.com/images/logo.png',
	  codeLanguages: '',
	  autosave: 'editor-content',
	  toolbar: [  'bold','code','ul','ol','image' ]
	});
	editor.on('selectionchanged', function() {
		$(".code-popover").hide();
	});

	// 提交数据
	$("#share_code").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		
	});
	$("#user_add_note").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		$('html, body').animate({
       	    scrollTop: $("#respond").offset().top
    	}, 200);
	});

	// 提交笔记
	var commentform=$('#commentform');
	commentform.prepend('<div id="comment-status" style="display:none;" ></div>');
	var statusdiv=$('#comment-status');
	
	commentform.submit(function(e){
		e.preventDefault();
		var noteContent = editor.getValue();
		// console.log(noteContent);
		noteContent = noteContent.replace(/<pre><code>/g,"<pre>");
		noteContent = noteContent.replace(/<\/code><\/pre>/g,"</pre>");
		
		// 系列化表单数据
		var comment_parent = 0;
		var is_user_logged_in = $("#is_user_logged_in").val();
		var comment_post_ID =  4014;
		var _wp_unfiltered_html_comment = $("#_wp_unfiltered_html_comment").val();
		var comment = noteContent;
		var author = $("#author").val();
		var url = $("#url").val();
		var email = $("#email").val();
		if(isBlank(author) && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入昵称！</p>').show();
		} else if(isBlank(email)  && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入邮箱！</p>').show();
		} else {
			// var formdata=commentform.serialize() + "&comment=" + noteContent ;
			// 添加状态信息
			statusdiv.html('<p>Processing...</p>').show();
			// 获取表单提交地址
			var formurl=commentform.attr('action');
			
			// 异步提交
			$.ajax({
					type: 'post',
					url: formurl,
					dataType:'json',
					data: {"comment_parent":comment_parent,"comment_post_ID":comment_post_ID, "_wp_unfiltered_html_comment":_wp_unfiltered_html_comment,"comment":comment,"url":url, "email":email,"author":author},
					error: function(XMLHttpRequest, textStatus, errorThrown){
					statusdiv.html('<p class="ajax-error" >数据不完整或表单提交太快了！</p>').show();
				},
				success: function(data, textStatus){
					if(data.errorno=="0") {
						$("#submit").prop('disabled', true);
						statusdiv.html('<p class="ajax-success" >笔记已提交审核，感谢分享笔记！</p>').show();
						alert('笔记已提交审核，感谢分享笔记！');
					}else{
						statusdiv.html('<p class="ajax-error" >'+data.msg+'</p>').show();
					}
					commentform.find('textarea[name=comment]').val('');
				}
			});
			setTimeout(function(){
		        $("#submit").prop('disabled', false);
		    }, 10*1000);
		}
		return false;

	});
	$(".comt-author").click(function() {
		href = $(this).children("a").attr("href");
		if(href.indexOf("/note/")!=-1) {
			var win = window.open(href, '_blank');
  			win.focus();
		}
	});
	$(".comt-meta span").hover(function(){
		$(this).children(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
		$(this).children(".tooltip").removeAttr("style");
	});
	/*
	$(".wrapper i").hover(function(){
		$(this).siblings(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
		$(this).siblings(".tooltip").css({ "opacity": 0, "pointer-events": "auto"});
	});
	*/
	//Upvote.create('runoobvote-id', {callback: vote_callback});
	var ajaxurl = 'https://www.runoob.com/wp-admin/admin-ajax.php';
	var callback = function(data) {
		//console.log($('#runoobvote-id').upvote('upvoted'));
		//console.log($('#runoobvote-id').upvote('downvoted'));
		//console.log(data);
		_vote_action = data.action;
		id_arr = data.id.split('-');
		um_id= id_arr[2];
		//console.log(um_id);
		
		var re = /^[1-9]+/;
		if (re.test(um_id)) { 
			var ajax_data = {
				_vote_action: _vote_action,
				action: "pinglun_zan",
				um_id: um_id,
				um_action: "ding"
			};
			//console.log(ajax_data);
			$.post(ajaxurl,ajax_data,function(status){
				//if(status.vote_num>999) {
				//	_voteHtml = '<span style="display: block; text-align: center;font-size: 20px; color: #6a737c; margin: 8px 0;">'+kFormatter(status.vote_num) +'</span>';
				//	$("#runoobvote-id-" + um_id + " .count").hide().after(_voteHtml);
				//}
				
			});
		}
	};
	if($('#comments').length && $('.upvotejs').length){
		$('.upvotejs').upvote({id: 4014, callback: callback});
	
		$.post(ajaxurl,{"action":"pinglun_zan","postid":4014},function(data){  
			$(data).each(function(key,value) {
				$("#runoobvote-id-" + value.commid + " .upvote").addClass(value.upvotejs_class);
				$("#runoobvote-id-" + value.commid + " .downvote").addClass(value.downvote_class);
				$("#runoobvote-id-" + value.commid + " .count").text(value.upvote_count);
			})
		},'json');
		
	}
	
	
});
function isBlank(str) {
    return (!str || /^\s*$/.test(str));
}
function kFormatter(num) {
	// return num;
    return Math.abs(num) > 999 ? Math.sign(num)*((Math.abs(num)/1000).toFixed(1)) + 'k' : Math.sign(num)*Math.abs(num)
}

</script>

<link rel="stylesheet" href="../0/qa.css?1.44">
<link rel="stylesheet" type="text/css" href="../0/simditor.min.css" />
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